Monofilament thread and method of making same



24, 1953' F. .1. M CARTHY 2,660,546

MONOFILAMENT THREAD AND METHOD OF MAKING SAME Filed July 17, 1952Patented Nov. 24, 1953 MONOFILAMENT THREAD, AND. METHOD OF" MAKING SAMEFrank J. McCarthy, Freeport, N. Y., assignor to Holland Mfg. Go.,-..Inc.,. Ncw;:Ynrk, Nil-Y2, a; 0.0132.- poration of New JerseyApplication July 17, 1952, Serlal No. 299,437

Claims. 1

Thisinvention relatesto amethod and composition for makingamonofilamentthread from,

a plurality of subfilamentthreads. In the sewing of textile material byconventional threads. having-a twist thereina great amount of frictionis generated by the twist thread passing through the eye of the needlewith the result that the temperatureof the needle is elevated sometimesto the point of being etxremely hot, thereby necessitating stopping thesewing operation or decreasing sewing speed.

It is an object of this invention to provide a monofilament threadcomposed of a plurality of subfilament threads, said monofilament threadhaving no or substantially no twist therein.

It is also an object of this invention to provide a thread which may *bepassed through the eye of a needle without raising the temperature ofthe needle to an undesirable degree during normal sewing speed.

It is a further object of this invention to provide a monofilamentthread whereby sewing speeds may be increased over those used in normaloperation without deleteriously effecting the temperature of the needleduring the sewing operation.

It is a further object of this invention to bond a plurality ofsubfilament threads to produce a monofilament with a minimum amount oftwist, thereby yielding a thread of increased strength permitting theuse of smaller needle sizes and smaller thread sizes for given purposesthan are commonly used.

This invention is described in conjunction with the accompanying drawingin which Fig. 1 is an elevation view broken away in part to show themanner of submerging a thread into a liquid bath;

Fig. 2 is a top plan view showing a plurality of spools being processed,and

Fig. 3 is a cross-section of the monofilament taken at the line 3-3 inFig. 1.

Referring to the drawings a thread I having substantially no twist or aminimum of twist and composed of a plurality of subfilaments is unwoundfrom a spool 2 positioned on a substantially upright support 3. Thethread I is drawn through a bath by a driven reel (not shown) over a rod4 located above the bath 5. The thread is then conducted beneath a guideroller 6 having circumferential recesses therein for receiving thethread, said guide roller being journaled on shaft 1 and submergedbeneath the surface of a liquid composition 8 disposed within the bath5. The thread upon passing through the composition bath 8 underneathguide roller 6 is then conducted to a. guide button. 9-. V The guidebutton Q-"is preferably; of porcelain and has an aperturei therein forreceiving the treated thread: A plu rality of guide buttons 0 may bedisposed in. a, support. IE3; saidzsupport,lir'being ataan elevas tionpreferably. above that of. rod Land/ adapted; so.,tha;tany liquid will?fall. back. from. said: guide.

buttons. 9-into. thabath. 5. As;.'shoWn1-.in Fig. 1'. bath dis:preferably :made of; two: wallsrformingr a v shaped.troughafoiznsupporting the; compost-.5 tion of this invention. Thethread after passing;

through guide button 9 is conducted into an oven II where an elevatedtemperature is maintained to drive off any solvent on the thread and toproduce a monofilament wherein the plurality of subfilaments are mergedso as to lose their prior individual identities.

The bath composition of this invention is an important feature thereof.When plastic filaments are used, for example, nylon filaments, they maybe bonded together by using a composition comprising from 1-32 parts byweight of phenol and from 1-12 parts by weight of nylon. The nylon usedto form the bath composition is preferably that known as superpolyamidenylon and is preferably prepared from a composition, for example, 264parts of hexamethylene diamine and 332 parts of adipic acid and 600parts of xylenol mixture, composed of three different isomeric xylenols.The term nylon as used herein is defined generically as the reactionproduct of a polyamine and a dibasic acid.

A specific formula used for the bath composition is:

32 parts by weight of phenol 12 parts nylon 1 part of pure acetic acid16 parts of 37% solution of formaldehyde 16 parts of xylene In preparingthe composition bath, the nylon is dissolved in the phenol and broughtto a slow boil. Then the formaldehyde solution is added. Next the aceticacid is added and the boiling is continued until a desired viscosity isobtained. Such a viscosity is about 1400 centipoises at F. Next thevessel is removed from the means used to heat the vessel and xylene isadded with constant stirring while the mixture is still hot. Thereuponthe reaction mass is allowed to cool. Before using the above preparedreaction mass or resin it is preferably diluted in the ratio of 1 partmethanol to 3 parts resin.

The methanol thinned resin is poured into the bath 5 and the thread I isrun there-through at a speed suitable to thoroughly wet the plurality 3of subfilaments so that upon drying in oven ll fusion of thesubfilaments into a common monofilament takes place.

In lieu of 37% solution of formaldehyde the para formaldehyde form maybe used. Also any anhydrous aldehyde equivalent to formaldehyde isoperable in this invention. Furthermore, in lieu of phenol, any aromaticphenol such as the cresols and the like may be used.

The composition of this invention may be modified by the addition of asoluble dye, whereupon the monofilament formed will be uniformly dyed toyield an evenly formed dyed monofilament thread.

Having described my invention, what I claim and desire to secure byLetters Patent is as follows:

1. The method of fusing a plurality of substantially untwisted textilefilaments to produce a monofilament sewing thread having substantiallyno twist comprising treating said plurality of filaments with a resincomposition comprising the reaction product of nylon, a phenol, and analde hyde.

2. The method of fusing a, plurality of substantially untwisted nylonfilaments to produce a monofilament sewing thread having substantiallyno twist comprising treating said plurality of filaments with a resincomposition comprising the reaction product of nylon, a phenol, and analdehyde.

3. The process of claim 2 wherein the phenol is phenol and the aldehydeis formaldehyde.

4. The method of claim 3 wherein the treating step consists of dippingthe plurality of filaments in a solution of said resin compositionfollowed by drying the dipped filaments at an elevated temperaturesufliciently high to induce fusion of the filaments to produce amonofilament.

5. A sewing thread comprising a plurality of nylon subfilaments fusedtogether with a nylon phenol formaldehyde composition to produce aunitary monofilament.

FRANK J. McCARTHY.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 1,591,705 Guay July 6, 1926 2,243,917 Owens June 3, 19412,277,602 Novak Mar. 24, 1942 2,292,442 Hanford Aug. 11, 1942 2,514,197Groten et al. July 4, 1950 2,522,526 Manning Sept. 19, 1950 2,574,221Modigliani Nov. 6, 1951 FOREIGN PATENTS Number Country Date 560,535Great Britain Apr. 7, 1944

1. THE METHOD OF FUSING A PLURALITY OF SUBSTANTIALLY UNTWISTED TEXTILEFILAMENTS TO PRODUCE A MONOFILAMENT SEWING THREAD HAVING SUBSTANTIALLYNOT TWIST COMPRISING TREATING SAID PLURALITY OF FILAMENTS WITH A RESINCOMPOSITION COMPRISING THE REACTION PRODUCT OF NYLON, A PHENOL, AND ANALDEHYDE.
 5. A SEWING THREAD COMPRISING A PLURALITY OF NYLONSUBFILAMENTS FUSED TOGETHER WITH A NYLON PHENOL FORMALDEHYDE COMPOSITIONTO PRODUCE A UNITARY MONOFILAMENT.